Safety-valve



J. L. LUBY. AND C. A. TREAT.

SAFETY VALVE.

APPLICATION FILED NOV-5.19M?- 1,33 1, 1 15. Patented Feb. 17, 1920.

/3 5 6 /7 1 /9 g if 0 \Q I 2 5% 7 i /4 74 /6 y 5 1 '/0 /Z A l2 /2 a? F .3 6; {if f- INVENTORS C. A 7kE/4 T AND v J.L. LUBK UNITED STATES PATENT OFFICE.

JOHN LOUIS LUBY AND CLIFFORD A. TREAT, OF DENVER, COLORADO, ASSIGNORS TO THE LIBERTY PRESSURE COOKER COMPANY,

A CORPORATION OF COLORADO.

SAFETY-VALVE.

Specification of Letters Patent.

Patented Feb. 17, 1920.

To all whom it may concern:

Be it known that we, JOHN LoUIs LUBY and CLIFFORD A. TREAT, citizens of the United States, residing at Denver, in the county of Denver and State of Colorado, have invented certain new and useful Improvements in Safety-Valves, of which the following is a specification.

This invention relates to safety-valves and more particularly to valves of the type used on pressure-cookers.

Pressure-cookers at present in common use have a safety-valve which automatically opens when the pressure in the vessel rises to a certain predetermined point, and in addition thereto, a blow-off cock which is used to reduce the pressure in the vessel before its lid is detached for the removal of its contents.

It is the primary object of the present invention to provide a valve-construction which performs the function of a safetyvalve to prevent the generation of dangerous pressures within the cooking vessel to which it is attached and which by a simple adjustment may be employed as a blow-off cock to reduce the pressure in the vessel to the minimum prior to the removal of its contents.

Another object of our invention is to pro vide a safety-valve which is of very simple construction and which has an adjustment to regulate the pressure at which it opens for the escape of steam from the vessel to which it is applied, and still another object of the invention is to provide a valve of this type in which all the component parts are permanently connected together.

The above and other objects, all of which will fully appear in the course of the following description, we attain by the construction and arrangement of parts shown in the accompanying drawings in the various views of which like parts are similarly designated, and in which- Figure 1 is a side elevation of our improved valve,

Fig. 2, a sectional elevation of the same, and

Fig. 3, a section taken on the line 3-3, Fig. 1.

Referring to the drawings by numerical reference characters, our combined safetyvalve and blow-0E cock is composed of an axially bored housing 2 provided at its lower end with an exteriorly screw-threaded nipple 3 by which it is secured inside a correspondingly threaded opening in the cover of the cooking vessel.

The housing has at its upper end, two oppositely disposed, upwardly projecting ears 4 and 5 which are grooved at their extremities for the reception of a. lever 6.

This lever consists of a bar which is fulcrumed in the groove of one of the ears, as at 7, and extends loosely for up and down movement in the groove of the other.

The bar carries at its free end, a handle 8 of nonconductive material to facilitate its adjustment and it has between this handle and the grooved ear beyond which it extends, a number of notches 9 for the attachment of a tension-spring 10 which is permanently attached to an a-pertured lug 12 projecting laterally from the housing adjacent its threaded nipple.

The spring has at its upper end a hook 13 by which it may be detachably fastened in any one of the notches of the lever in order to regulate the pressure at which the'valve is lifted for the escape of steam from the vessel to which it is applied, and the different pressures are indicated on the lever adj acent the respective notches by figures which i in the drawings have been designated by the reference characters 14.

The edge of the axial bore of the housing at the upper end thereof, constitutes the seat of a valve 15 composed of a rounded body 16 at the end of a stem 17 by which it is pivotally connected with the portion of the lever extending between the two ears.

The groove in the ear of the housing through which the lever loosely extends for up and down movement has at one of its sides, a recess to provide a rest 18 for the lever in a raised position.

This rest is used when the device is employed to perform the function of a blowoff cock, to hold the lever 15 off its seat against the pressure of the spring and thereby permit of the escape of steam .through the bore of the housing.

Having thus described the mechanical construction of our combined safety-valve and blow-off cock, its operation will be readily understood.

The user of the pressure cooker sets the spring in the notch of the lever corresponding with the pressure at which it is desired to effect the automatic escape of steam generated in the vessel, it being understood that the highest pressure indicated on the lever is steam and automatically preventing the generation of dangerous pressures.

When the contents of the cooker have been subjected during the required length of time,

to the influence of the steam, the valve is.

lifted from its seat by raising the lever in V the grooved ear 5 and placing it upon the rest 18 thereof. The steam is thus permitted to escape until the pressure in the vessel 7 is reduced to the minimum after which the cover of the vessel may be safely removed for the removal of its contents.

It will be seen that after the spring is detached from the notch of the lever, the valve is readily separated from its seat for cleaning purposes, by means of the non-conducting handle and without the necessity of touching the hot metal parts.

It will also be noticed that the different parts of the valve-construction are all permanently connected with the housing so that they may be readily replaced in their operative position without separate adjustment and manipulatlon.

Having thus described our invention what we claim and desire to secure by Letters- Patent is:

1. A safety-valve of the character described comprising a housing having a vertical passage, a valve-seat at the upper end thereof and an upwardly projecting ear, a

lever fulcrumed on the ear and having a plurality of notches for the attachment of a spring at difierent distances from its fulcrum, a valve pivoted on the lever and rest-.

ing upon the eat, and a tension-spring having means for its attachment in any one of the notches of the lever.

2. A safety-valve of the character described comprising a housing having a vertical passage, a valve-seat at the upper ends thereof, and an upwardly extendlng car, a lever fulcrumed on the ear, a valve pivoted on the lever and resting upon the seat, and a tension spring attached to the lever, the housing having a rest for the support of the rest for the support of the lever in an adjusted position in which the valve is raised from its seat.

l. A safety-valve of the character described comprising a housing having a vertical passage, a valve-seat at the upper end thereof, and upwardly extending ears one of which has a groove and a rest at a side thereof, a lever fulcrumed on one of the ears and extending loosely through the groove of the other, a valve pivoted on the lever and resting upon the seat, and a tension-spring attached to the lever, the lever being capable of lateral movement for its adjustment to a position in whch it engages said rest.

5. A safety-valve of the character described comprising a housing having a vertical passage and upwardly projecting ears at opposite sides of an end thereof, a lever fulcrumed at one end on one of said ears and extending loosely through a groove in the valve consisting of a rounded body normally engaging the housing at the upper end of the passage and a rigid stem pivotally connected with the lever.

6. A safety valve of the character described comprising a housing having a vertical passage, a valve-seat, and a lever seat, a lever fulcrumed at one end on the housing, a spring yieldingly holding the lever in engagement with the lever-seat, and a valve consisting of a rounded body normally engaging the valve-seat, and a rigid stem pivotally connected with the lever.

In testimony whereof we have affixed our signatures.

- 1 JOHN LOUIS LUBY.

CLIFFORD A. TREAT. 

